With current electromechanical low voltage switchgears, in particular of installation size S0/S00, a reversing locking device for the consumer branches is affected in an individual setup outside of the device. Two contactors are herewith wired up in parallel and a circuit breaker is to this end connected in series. The locking device is realized by additional parts, for instance an armature and a bearing, which are mounted between contactor drives and act on the contact-maker holder. With electrical reversing contactors, the locking device acts on the armature of the contactor drives for the mutual blocking. I.e. the reversing locking device for mutually blocking the main drives prevents simultaneous closure of the main contacts for changing the direction of rotation.
DE 691 10 195 T2 discloses an electrical reversing contactor, comprising a mechanical locking device for the moveable armature parts of the two contactor drives. The electrical reversing contactor comprises a housing, in which two cavities are provided, which each comprise a system of switching parts with its own electromechanical controller. I.e. the magnetic drive of the one system is arranged separately from the magnetic drive of the other system. A separate magnetic chamber is provided for each magnetic drive. A moveable locking part is provided between the two cavities, which prevents a simultaneous movement of the moveable contact holders which are coupled to the moveable armature parts, of the two magnetic drives.
The disadvantages with an electrical reversing contactor of this type are the complicated structure of the mechanical locking device and the indirect locking device of the magnetic drives. Furthermore, an electrical reversing contactor of this type is relatively large in terms of its exterior dimensions, since two separate magnetic chambers are provided in the housing of the electrical reversing contactor.